Rotary tool



Jan. 18, 1944. P. VAN SITTERT E1; AL 2,

ROTARY TOOL Filed Aug. 27, 1941 2 Sheets-Sheet l INVENTORS PAUL VANJITTERT AND/Q5 W -11 LEV BY W ATTORNEY Jan. 18, 1944. P. VAN SITTERTETAL 2,339,530

ROTARY TOOL Filed Aug. 2'7, 1941 2 Sheets-Sheet 2 INVENTOR PAUL 144W 57-5 AND/? W 'J. LE 1 Y ATTORNEY Patented Jan. 18, 1944 ROTARY TOOL IPaul Van Sitter-t, Shaker Heights, and-Andrew I.

Lev, Garfield Heights, Ohio, assignors to The Cleveland Pneumatic Tool,Company, Cleveland. Ohio, a corporation of Ohio Application August 27,1941, Serial No. 408,546

' 14 Claims.

This invention relates broadly to a portable rotary impact tool, butmore particularly to an impact producing mechanism for such a tool.

One object of this invention is to produc a rotary impact tool with animproved impact delivering mechanism capable under certain conditions ofoperation of remaining inoperative anism capable of delivering impactsof an in- .tensity materially greater than that heretofore delivered byportable rotary impact tools of similar size and power consumption.

Another object of this invention i th provision in a rotary impact toolof means enabling positive engagement of the impact delivering memberwith component driven parts, thereby allowing for the provisionofadequate impact delivering and receiving surfaces adapted to resistpremature wear and breakage.

Another object of this invention i to produce an improved rotary impactdelivering mechanism for use with a reversible rotary motor.

.Still another object of this invention is to produce a portablereversible rotary'impact tool Fig. 8 is a cross sectional view taken ina plane indicated by line 8-8 in Fig. 1.

' side of the partition in Fig. 1, is formed with an which is compact,strong, durable and efiicient.

' vention.

Fig. 2 is va view similar to Fig. '1 but showing some of the parts inanother position.

Fig. 3 is a cross sectional view taken in a plane indicated by 3-3 inFig. 1.

Fig. 4 is a cross sectional view taken in a plane indicated by line 44in Fig. 2.

Fig. 9 is a cross sectional view taken in a plane indicated by line 9-9in Fig. 1.

Fig. 10 is a cross sectional view taken in a plane indicated by lineIll-J0 in Fig. 1.

Fig. 11 is a cross sectional view taken in a plane indicated by linellll in Fig. 2.

Referring to the drawings, there is shown the front end of a motorhousing 20 having mounted therein a'fluid actuated rotary motor of thereversible type. Since the motor forms no part of the present invention,no illustration or description thereof is thought necessary other thanpointing out that the motor may be of any suitable type and of a sizeand weight adaptable for use with the device to be described so as toform therewith'a portable tool. The front end of the motor housing 20 isexternally threaded as at 2| to receive a substantially 'cup shapedcasing 22 having housed therein the mechanism to be hereinafterdescribed. an

A driving shaft 23 operatively associated with the motor within thehousing 20 is journaled within a housing partition 24 and, onth leftintegral collar 25, which collar is provided with twodiametrically'opposed longitudinally extending and open ended grooves 26and 21, each groove having slidably mounted within its side walls aspring pressed plunger 28 having its outward slidable movement limitedby a cross pin 29 engaging the end of a flat 30 provided on the pin 28intermediate its ends. From the collar 25, the shaft 23 extends into thecasing 22 and has secured thereon by a cross pin 3! a ring 32 formedwith two diametrically opposed notches 33, each notch being of apredetermined width and having outwardly inclined side walls 34. Im-'mediately below the ring 32, the shaft 23 is formed with a reducedportion 35 having mounted thereon a cylindrical, relatively heavy memberhereinafter'referred to as a driving head 36 which has its end adjacentthe collar 25 provided with two lugs 6i and 62 longitudinally extendinginto the grooves 26 and 21 of the col- Fig. 5 is a side-'view of some ofthe part in 7 their relative position assumed in the mechanism 'la'r 25,each lug being located between two plungers 28 protruding from the sidewalls of the groove. That same end of the driving head is also formedwith a counterbore 31 accommodating the ring 32 mounted on the shaft 23.Ex-' teriorly, the driving head 36 is provided with two diametricallyopposed guideway 38 extending longitudinally from one to the other endof the head, each guideway having a key or do 33 slidabiy mountedtherein flush with the peripheral wall of the driving head and retainedwithinthe guideway 38 by a cylindrical sleeve to fitted over the drivinghead 33. The guideways so are deep enough to break into the counterbore37 of the driving head 33. Each dog 33 has its end portion adjacent thecollar 25 of the shaft 23 carrying a stub shaft ti extending into thecounterbore 37 where it carries a roller s2 normally located within oneof the notches 33 provided in the ring 32. The inner longitudinal wallof each dog is provided with an elongated groove 53 accommodating acompression spring it having one end resting against the correspondingend of the groove while the other end rests on a pin 65 carried by thedriving head 36 and extending therefrom into the groove 33, thus thespring td constantly urges the dog 39 away from the collar 25, whichmovement is limited by the engagement of the roller 42 with the bottomof the notch 33 of the ring 32.

Rotatable within the front end of the casin 22, there is a driven headcomprising a plate 43 resting on the bottom of the casing 22 and havinga shaft portion 41 extending therefrom through the casing, which shaftis terminated by a hexagon head 43 fitting within one end of a socketwrench 49 adapted to fit over the work represented by a nut 30positioned for rotation on a bolt iii. The plate 43 is coaxial with thedriving head 33 and has two diametrically opposed lugs or clutch teeth32 extending from the inner side thereof toward the driving head 33,which lugs are engageable by the dogs 33 to form a releasable clutch.Radially the lugs 32 extend from the outside edge'of the plate 43 partlytoward the center thereof and'have located between them a disk 33journaled on a small shaft 34 extending from the plate or driven head 33into the driving head to assist the shaft 33 in rotatably supporting thedriving head. The disk 53 is provided with an internal ring gear 33accommodated within a shallow counterbore .33 in the driving head 33.Meshing with the Fig. 10, that is with its grooves 63 in position toallow slidable movement of the dogs as through the grooves intoengagement with'the lugs 52 of the driven head as. thereby transmittingrotation from the driving to the driven head and finally to the nut 56'.In this normal driving position of the dogs 33, the rollers 62 carriedby the dogs are positioned in the notches 233 as shown in Fig. 5. Duringthis rotation of the driving and driven heads, the gears 51 carried bythe driving head will rotate therewith while remaining on theirrespective shafts 58, and due to their engagement with the ring gear BBwill transrnit rotation to the disk 53 at the same rate of speed as thatof the heads, thereby preventing rotation of, the disk groovestilrelative to the dogs 39.

When the nut Kill is about set, its resistance to rotation will resultin a rapid deceleration of the driven head :33 and driving head 33 whilethe shaft 23 is still rotated at its original rate of speed,therebycausing relative rotation between the driving head 33 and theshaft 23 which is possible by the. inward movement of the driving springpressed plungers 28 within the side walls or the grooves 26 and 21 andlimited by the engagement of the lugs 3| and 62 with the side walls orthe grooves 23 and 21 as shown in Fig. 4. This limited relative rotationwill cause the ring 32 carried by the shaft 23 torotate relative to therolls 42- carried by the dogs 39, resulting in a camming action of theside walls 34 of the notches 33 on the rollers 42 for moving the rollersout of the notches and cause them to rest on the end wall of the ring 32adjacent the collar 23. This outward movement of the roll- V are is ofcourse. transmitted to the dogs 33, cansextend radially inward beyondthe lugs 32 and I consequently inside of the outer marginal edge of thedisk to rest on the disk as shown in Fig. 2. Inthickness, the disk 33exceeds somewhat the height of the lugs 32, thereby preventin engagementof the dogs 33 with the lugs 32 when the dogs rest on the disk 33.Externally, the disk 33 is provided withtwo diametrically 'opposedlongitudinally extending grooves 33 through which the dogs 39 are freeto slide for engagement with the lug 32 aswill be explained later.

In the operation of the mechanism, rotation in one or the otherdirection is imparted to the shaft 23 by the motor housed within thehousing 20. Assuming now that the rotation of the shaft'23 is in theclockwise direction when viewed from the motor end of the tool, that isin the clockwise direction in Figs. 3 and 4. The rotation of the shaft23 is transmitted to the driving head 33 by the spring pressed plungers23 active on ing disengagement or release of the dogs from the lugs 32of the driven head 43 and enabling free rotation of the driving head 33relative to Y the now stationary driven head 43. Immediately after thedisengagement of the dogs 33, the gears 31 rotated around the nowstationary pinion 33 will transmit rotation to the ring gear 33 andconsequently to the disk 33 at a rate of speed calculated to be somewhatfaster than that of the driving head. In the present construction, thegears 33, 31 and 33 are calculated to result in three and one-halfrevolutions of the disk 33 for each three revolutions of the drivinghead 33. This predetermined differential rate of rotation between thedriving head and the disk 53 will result in the grooves 33 of the diskto the lugs BI and 32 of the driving head as shown in Fig. 3, the lugs3| and 32 being normally maintained central within the grooves 23 and 21by the spring pressed ungers 28.

Normally, the disk 3 is located as shown in be moved out of thelongitudinal path of the dogs 39, thereby preventing engagement of thedogs 39 with the lugs 52 and consequently enabling the driving head toreach its maximum rotary speed before reengagement of its dogs 33 withthe lugs 32.

During the rotation of the driving head relative to the driven head, thelugs BI and 32 of the driving head will gradually be moved in centralposition within the grooves 23 and 210! the shaft collar 23 by theaction of the depressed spring pressed plungers 28 on the lugs ill and32,- thereby positioning the rollers 42 directly above but not in thenotches 33.

Dining this axial movement of the dogs 39. the rollers 42 carried by thedogs will again be moved into the notches 33 of the disk 32 as shown inFig. 5.

As the dogs 39 finally reach the lugs 52, the inertia of the drivinghead 36, which head has now reached its maximum rotary speed, istransmitted to the dogs 39 causing them to deliver a powerful rotaryimpact to the lugs 52 which is communicated to the socket wrench 49 andresuits in imparting a relatively strong short impulse to turn the nut.when the engagement or impact takes place, resistance to rotation of thedriven head will again be transmitted to the driving head which willmomentarily stop abruptly, causing the shaft 23 to rotate relative tothe 'driving head from the position in Fig. 3 to that in Fig. 4 andagain causing upward movement of the rollers 42 from the position inFig. 5 to that in Fig. 6 for disengaging the dogs 39 from the lugs 52.These cycles follow each other in rapid succession and are continueduntil the operator by experience knows that the nut has been driven homeas tightly as desired, whereupon the motor housed within the housing 20is stopped and the tool removed from the nut.

When it is desired to use the tool for removing nuts from bolts, themotor within the housing 20 maybe reversed for imparting rotation to theshaft 23 in the other direction. The engagement and disengagement of theclutch comprising the dogs 39 and lugs 52 occurs in the manner abovedescribed, since all of the operating parts are double-acting andfunction exactly the same regardless of the direction of rotation.However, in running the tool in such reverse direction the impacts occurat the start of the operation and afterthe nut is sufliciently loosenedthe driven head may turn continuously instead of intermittently.

Although the foregoing description is necesarily of a detailedcharacter, in order to completely set forth the invention, it is to beunderstood that the specific terminology is not intended to berestrictive or confining and it is to be further understood that variousrearrangements of parts and modifications of structural detail may beresorted to without departing from the scope or spirit of the inventionas herein claimed,

We claim:

1. In a power actuated tool of the class described, a rotary drivinghead, a driven head, clutch means between said heads capable of re-\lease to enable rotation of said driving head relative to said drivenhead, means responsive to a predetermined resistance to rotation of saiddriven head for efiecting said release, means including a train of gearsdrivenly associated with said driving head for maintaining said clutchmeans in released position during more than one revolution of saiddriving head relative to said driven head, and means effectingsubsequent reengagement of said clutch means.

2. In a power actuated tool of the class described, a prime mover, adriving and a driven head, clutch means between said heads capableof-release to enable rotation of the driving head relative to the drivenhead, connecting means between said prime mover and driving headincluding means enabling limited relative rotation therebetween uponpredetermined resistance to rotation of aid driving head, meansresponsive to said limited relative rotation for eifecting said release,means responsive to the rotation of the driving head relative to saiddriven head for maintaining said clutch means in released positionduring more than one revolution of said driving head, and meanseffecting subsequent reengagement of said clutch means.

3. In a power actuated tool of the class described, a prime mover, adriving and a driven head, clutch means between said heads capable saidclutch means in released position during more than one revolution ofsaid driving head, and mean effecting subsequent reengagement of saidclutch means.

4. In a power actuated tool 'of the class de scribed, a prime moverrotatable in either direction, a driving and a driven head, clutch meansbetween said heads capable of release to enable rotation of the drivinghead relative to the driven head, a resilient connection between saidprime mover and driving head enabling limited rotation therebetween uponpredetermined resistance to rotation of said driven head irrespective ofthe direction of rotation of said prime mover, cam means between saidprime mover and driving head responsive to said limited relativerotation for effecting said release, means deriving motion from therotation of said driving head relative to said driven head formaintaining said clutch means in released position during more than onerevolution of said driving head, and means effecting subsequentreengagement of said clutch means.

5; In a power tool of the class described, a rotary driving head, adriven head, teeth on said driven head, longitudinally slidable dogscarried by said driving head engageable with said teeth for transmittingrotation from. said driving to said driven head but capable of releaseto enable relative rotation therebetween, a prime mover for said drivinghead, a resilient connection between said driving head and prime moverenabling limited relative rotation therebetween upon predeterminedresistance to rotation of said driven head,

cam means between said dogs and prime mover responsive to said limitedrelative rotation for efiecting aid release, means deriving motion fromthe relative rotation between said heads for maintaining said dogs inreleased position during more 6. In a power tool of the class described,including a drive shaft and means for operating,

the same, a rotary driving head mounted on said shaft, a driven headoperably associated with said driving head, clutch means between saidheads capable of release to enable relative rotation therebetween, meansresponsive to a predetermined resistance to rotation of said driven headfor effecting said release, said clutch means including spaced lugsformed on said driven head, longitudinally slidable dogs carried by saiddriv- 0 ing head engageable with said lugs for transmitting motion' fromsaid driving head to said driven head, means carried by said driven headbetween said spaced lugs and operable by said driving head formaintaining said clutch means in reof said driving head relative to saiddriven head, and means effecting subsequent reengagement of said clutchmeans.

7. In a power tool of the class described, including a drive shaft andmeans for operating the same, a rotary driving head mounted on saidshaft, a driven head operably associated with said driving head, clutchmeans between said heads capable of release to enable relative rotationtherebetween, means responsive to a predetermined resistance to rotationof said driven head for effecting said release, said clutch meansincluding spaced lugs formed on said driven head, longitudinallyslidable dogs carried by said driving head engageable with said lugs fortransmitting motion from said driving head to said driven head, a discrotatably carried by said driven head and supported between said lugs,said disc having grooves through which said dogs extend for engagementwith said lugs, means on said driving head cooperating with saidrotatable disc for maintaining said lugs and dogs in released positionduring more than one revolution of said driving head relative to saiddriven head, and means effecting subsequent reengagement of said clutchmeans.

8. In a power tool of the class described, in-

cluding a drive shaft and means for operating the same, a rotary drivinghead mounted on said shaft, a driven head operably associated with saiddriving head, clutch means between said heads capable of release toenable relative rotation therebetween, means responsive to apredetermined resistance to rotation of said driven head for effectingsaid release, said clutch means including spaced lugs formed on saiddriven head, longitudinally slidable dogs carried by said driving headengageable with said lugs for transmitting motion from said driving headto said driven head, a disc rotatably carried by said driven head andsupported between said lugs, said disc having grooves through which saiddogs extend for engagement with said lugs, means including a train ofgears drivenly associated with said driving head and cooperating withsaid rotatable disc for maintaining said lugs and dogs in releasedposition during more than one revolution of said driving head relativeto said driven head, and means effecting subsequent reengagement of saidclutch means.

9. In a power tool of the class described, including a drive shaft andmeans for operating the same, a driving head mounted on said shaft, adriven head operably associated with said driving head, clutch meansbetween said heads capable of release to enable relative rotationtherebetween, means responsive to a predetermined resistance to rotationof said driven head for effecting said release, a collar on said shaftand being formed with diametrically opposed grooves, resilient means insaid grooves for connecting said driving head andshaft enabling limitedrelative rotation therebetween upon predetermined resistance to rotationof said driven head, means deriving motion from the rotation of saiddriving head relative to saiddriven head for maintaining said clutchmeans in released position during more than one revolution of saiddriving head, and means effecting subsequent reengagement of said clutchmeans.

10, In a power tool of the class described, including a drive haft andmeans for operating the same, a driving head mounted on said shaft, a

driven head operably associated with said driving Y assasso a minedresistance of rotation of said driven head.

of release to enable relative rotation therebetween, means responsive toa predetermined resistance torotation of said driven head for eflectingsaid release, a collar on said shaft and being formed with diametricallyopposed grooves, a pair of spring pressed plungers siidably mounted inspaced relation within said grooves, said driving head having a pair oflugs extending into said grooves between said pair of plungers ,forconnecting said driving head and shaft and enabling limited relativerotation therebetween upon pre- 7 tion of said driving head, and meanseffecting subsequent reengagement of said clutch means.

11. In a power tool of the-class described, including a drive shaft andmeans for operating the same, a rotarydriving head mounted on saidshaft, a driven head operably associated with said driving head, clutchmean betweensaid heads capable of release to enable relative rotationtherebetween, means responsive to a predeterfor effecting said release,said clutch means including spaced lugs formed on said driven head,longitudinally slidable dogs carried by said driving head engageablewithsaid lugs for transmitting motion from aid driving head to said drivenhead, a resilient connection between said driving head and shaftenabling limited relative rotation therebetween upon predeterminedresistance to rotation of said driven head, a ring on said shaft morethan one revolution of said driving head,

and means effecting subsequent reengagement of said clutch means.

12. In a power tool of the class described, a rotary driving head, adriven head, clutch means between said heads capable of release toenable relative rotation therebetween, means responsive to apredetermined resistance to rotation of said driven head for effectingsaid release, means drivenly associated with said driving head, controlmeans carried by said driven head and cooperating with said drivenlyassociated means deriving motion from said relative rotation formaintaining said clutch means in released position during more than onerevolution of said driving head relative to said driven head, and meanson said control means positionable for enabling subsequent reengagementof said clutch means.

13. .In a power tool of the class described, a rotary driving head, adriven head, clutch means between aid heads capable of release to enablerelative rotation therebetween, means responsive to a predeterminedresistance to rotation of said said driven head for effecting saidrelease, means drivenly associated with said driving head, means carriedby said driven head and cooperating with said drivenly associatedmeansderiving motion from said relative rotation for maintaining saidclutch means in released position during more.

- than one revolution of said driving head relative to said driven head,and means effecting subsequent reengagement of said clutch means. 14. Ina power tool of the class described, a

by said driven head and cooperating with said drivenly associated meansderiving motion from said relative rotation for maintaining said clutchmeans in released position during more than one revolution of saiddriving head relative to said driven head, and means effectingsubsequent reengagement of said cliitch means.

, PAUL VAN SIT'IERT.

'ANDREW J. LEV.

